The present invention relates to a semiconductor manufacturing technique, and in particular, to an effective technique applied to enhancement of the reliability of semiconductor devices having small semiconductor chips arranged at narrow pad pitches.
In Japanese Patent Laid-Open No. 8-116012, No. 5-160304, No. 5-36862, No. 11-289040, No. 11-514149, No. 7-153890, No. 6-291217 and No. 5-235246, there are disclosed techniques for fixing inner leads to metal sheets and ceramic sheets via adhesives or the like.
Firstly, in Japanese Patent Laid-Open No. 8-116012, there is disclosed a resin-sealing type semiconductor device in which an aluminum sheet is used as a heat radiation plate and the inner lead is fixed to the aluminum sheet via adhesives by providing an insulation layer on a surface of the aluminum sheet. There are described objects of improving heat-radiating properties, reducing material cost, and shortening manufacturing time.
In Japanese Patent Laid-Open No. 5-160304, there is disclosed a semiconductor device having a construction in which an aluminum sheet is used as a heat radiation plate and leads are affixed to the aluminum sheet via adhesives as an object of improving heat properties.
In Japanese Patent Laid-Open No. 5-36862, there is disclosed a semiconductor device having a construction in which a ceramic sheet is affixed to inner leads. Heat generated from semiconductor chips is discharged into the exterior thereof through ceramic sheets and inner leads to thereby improve heat-radiating properties of the semiconductor device.
In Japanese Patent Laid-Open No. 11-289040, there are disclosed lead frames to which inner leads are joined at one surface of a heat radiation plate through an electrical insulation layer and adhesive layer, and a semiconductor device using these lead frames. There are described objects of improving the quality and reducing the manufacturing cost thereof.
In Japanese Patent Laid-Open No. 11-514149, there is disclosed an electronic package having a construction in which semiconductor chips and leads are fixed to a heat slug, on the surface of which electric insulating anode treated coating is provided. There is described an object of improving the heat properties thereof.
In Japanese Patent Laid-Open No. 7-153890, there is disclosed a lead frame for a semiconductor device in which inner leads are fixed to heat radiation plates via adhesives, the heat radiation plates each comprising a metal sheet on which insulation treatment is treated. There are described objects of attaining improvement of heat radiating properties, high speed of signal processing, and long life of the semiconductor device by this lead frame.
In Japanese Patent Laid-Open No. 6-291217, there is disclosed a heat-dissipation type lead frame in which a ceramic sheet is used as a heat radiation plate and inner leads are fixed to this ceramic plate via adhesives. There are described objects of not only suppressing residual stress generated by heat but also preventing a shape of the frame from being deformed at the manufacturing stages thereof when this lead frame has a package structure.
In Japanese Patent Laid-Open No. 5-235246, there is disclosed a semiconductor device of a construction in which a main surface of each semiconductor chip is fixed to one surface of an insulation tape via adhesives, and each inner lead is fixed to the other surface via the adhesives, and each semiconductor chip surface electrode is exposed from each hole of a insulation tape to connect the inner leads and the surface electrodes via said holes by wires. There are described objects of increasing the degree of design freedom of chips and attaining high speed of signal transmission.